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The Upper Jurassic--Lower Cretaceous Berdiga Formation of the Eastern Pontides, Turkey, represents a carbonate platform succession composed of pervasively dolomitized intra-shelf to deep-shelf facies. In this area, polymetallic deposits occur as veins and lenses within the Berdiga Formation in close proximity to its upper contact with the overlying formation. Three different types of replacive dolomites occur in the formation: (i) microcrystalline dolomite, (ii) fabric-preserving dolomite, and (iii) fabric-destructive dolomite. Replacive dolomites are Ca rich and nonstoichiometric ([Ca.sub.56]-58Mg42-44) and are characterized by a pronounced negative shift in oxygen (-11.38[per thousand] to -4.05[per thousand] Vienna Pee Dee Belemnite (VPDB)), [delta][.sup.13]C values of 0.69[per thousand] to 3.13[per thousand] VPDB, radiogenic [.sup.87]Sr/[.sup.86]Sr ratios (0.70753 to 0.70884), and extremely high Fe (2727-21053 ppm) and Mn (1548-27 726 ppm) contents. All dolomite samples have low Y/Ho ratios (23-40), and they also contain highly variable contents of rare earth elements (REE) (7-41). REE patterns of dolomites normalized to Post-Archean Australian shale show a distinct positive Eu anomaly (1.3-2.1) and slightly flattened Ce anomalies (0.8-1.1). Integration of petrographic and geochemical studies reveals the history of a variety of diagenetic processes highly affected by hydrothermal alteration, which include dolomitization, recrystallization, dissolution, silicification, and pyrite mineralization associated with the emplacement of the polymetallic mineralization. La Formation de Berdiga du Jurassique superieur-Cretace inferieur des Pontides orientales (Turquie) represente une sequence de plateforme carbonatee comprenant des facies intensement dolomitises allant de la plateforme interne a la plateforme profonde. Dans cette region, des gisements polymetalliques sont presents sous forme de filons et lentilles dans la Formation de Berdiga, tout pres de son contact avec la formation sus-jacente. Trois types de dolomite de remplacement sont presents dans la formation, a savoir : (i) de la dolomite microcristalline, (ii) de la dolomite preservant les fabriques et (iii) de la dolomite qui detruit les fabriques. Les dolomites de remplacement sont riches en Ca et non stoechiometriques ([Ca.sub.56-58][Mg.sub.42-44]) et elles sont caracterisees par un deplacement negatif prononce des valeurs d'isotopes d'oxygene (de -11,38 [per thousand] a -4,05 [per thousand] VPDB), des valeurs de [delta][.sup.13]C de 0,69 [per thousand] a 3,13 [per thousand] VPDB, des rapports [.sup.87]Sr/[.sup.86]Sr radiogeniques (de 0,70753 a 0,70884) et des concentrations en Fe (2727-21 053 ppm) et en Mn (1548-27 726 ppm) extremement elevees. Tous les echantillons de dolomite presentent des rapports Y/Ho faibles (de 23 a 40) et ont aussi des concentrations de terres rates (ETR) tres variables (de 7 a 41). Les spectres d'ETR des dolomites normalisees au PAAS presentent une nette anomalie positive d'Eu (de 1,3 a 2,1) et des anomalies de Ce legerement aplanies (de 0,8 a 1,1). L'integration d'etudes petrographiques et geochimiques fait ressortir l'histoire de differents processus diagenetiques fortement influences par l'alteration hydrothermale, dont la dolomitisation, la recristallisation, la dissolution, la silicification et la pyritisation associees a la mise en place de la mineralisation polymetallique. [Traduit par la Redaction], Introduction Dolomite [(CaMg(C[O.sub.3]).sub.2]) is a common diagenetic mineral. How dolomite is formed and altered are still matters of debate (e.g., Budd 1997; Al-Aasm et al. 2000; Warren 2000; Machel 2004; [...]

Objective: Paraoxonase1 (PON1), exhibits both esterase activity (PON1-AREase) and homocysteine thiolactonase activity (PON1-HTLase) which respectively prevent LDL oxidation and detoxify homocysteine thiolactone (HTL). Platelet-activating factor-acetylhydrolase (PAF-AH) is an antioxidant enzyme preventing LDL oxidation by hydrolysis of oxidized phospholipids. Both of these enzymes exhibit a proatherogenic role. ADMA is an endogenous inhibitor of nitric oxide (NO) synthesis causing endothelial dysfunction. The aim was to compare non-obese PCOS patients with a BMI matched control group using the following characteristics: serum PON1-HTLase, ADMA, PAF-AH, and lipid and hormonal parameters. Results: 77 women with PCOS and 25 healthy subject were recruited for this study, The controls were non-obese BMI and age matched with the patients. There were no significant differences with respect to age, BMI, FSH, free testosterone, DHEA, androstenadion, total cholesterol, triglycerides, HDL, LDL, VLDL, fasting glucose/insulin ratio and HOMA-IR among the groups ( p > 0.05). However, total testosterone and fasting glucose levels were significantly higher in the PCOS group ( p < 0.05). On the other hand, PON1-HTLase levels (39.6 ± 5.77 vs. 33.8 ± 8.2, p = 0.02) were significantly lower in the PCOS group while ADMA levels (1.14 ± 0.6 vs. 3.37 ± 6.4, p = 0.004) were significantly higher in the PCOS group. However, there was no significant difference in PAF-AH activity among the groups Conclusions: Decreased PON1-HTLase and increased ADMA levels might be a relevant marker for the development of future atherosclerotic heart disease (AHD) in non-obese PCOS patients. Further studies are needed to confirm our results. [ABSTRACT FROM AUTHOR]